Pine wilt disease: a short review of worldwide research

This article summarizes the results of the research papers presented at the International Symposium on pine wilt disease (IUFRO Working Party Meeting 4.04.03) held in July 2009, at Nanjing, China. The general topics covered were on pine wilt disease (PWD), its causal organism, the pinewood nematode (PWN) Bursaphelenchus xylophilus, plus other PWN-associated microorganisms that play a significant role in PWD such as bacteria (e.g. Pseudomonas fluorescens). Most of the papers that are reviewed are based on work on PWD-PWN in East Asia and Russia. Specific topics covered include: 1) the fundamental conceptions of PWD development, 2) pathogenicity, 3) host-parasite relationships including the histopathology of diseased conifers and the role of toxins from bacteria-nematode ecto-symbionts, 4) PWN life cycle and transmission, 5) B. xylophilus dissemination models, 6) associations (with other nematodes), 7) diagnostics, 8) quarantine and control of the PWN and 9) biocontrol of the PWN.     

Evaluation of cold resistance of ornamental species for planting as urban rooftop greening

Rooftop gardening or green roof establishment, one of the methods of afforestation for urban greening, has many benefits for the environment, the economy and urban landscapes. Various environmental stresses including heat, strong wind, sunshine and cold prevent most plants from growing well in extensive green roof systems. For the establishment of urban rooftop gardening in Beijing, we evaluated 13 ornamental plant species [Berberis thunbergii ‘Atropurea Nana’, Euonymus fortune (Turcz.) Hand., Viburnum dilatatum Thunb., Cotinus coggygria Scop., Swida alba Opiz., Weigela florida (Bunge.) A. DC., Jasminum nudiflorum Lindl., Euonymus japonicus Thunb., Euonymus japonicus ‘Cuzhi’, Buddleja davidii Franch., Pyracantha fortuneana (Maxim.) Li., Ligustrum lucidum Ait. and Spiraea salicifolia L.] for greening of flat rooftops. We obtained three indices concerning cold resistance, i.e., electrical conductivity of leaves, amounts of soluble sugars and amounts of free proline, providing a theoretical basis for selection of plants fit for roof and balcony greening. The results show that the six species P. fortuneana (Maxim.) Li., B. thunbergii ‘Atropurea Nana’, J. nudiflorum Lindl., E. fortune (Turcz.) Hand., E. japonicus Thunb. and E. japonicus ‘Cuzhi’ are excellent plants for rooftop gardening, judging from their strong ability in cold resistance. Plants such as L. lucidum Ait., C. coggygria Scop. and W. florida (Bunge) A. DC. showed a medium ability in cold resistance. However, these species can be used in roof and balcony greening after intensive management or acclimatization of variety. The ability to resist cold of plants such as W. florida (Bunge) A. DC., S. salicifolia L., V. rhytidophyllum and S. alba Opiz. (Cornus alba L.) was found to be rather weak. Therefore, cold-proof measures are recommended when using these species.     

Segregation of <Emphasis Type="Italic">Eucalyptus tereticornis</Emphasis> Sm. clones for properties relevant to solid wood products

Introduction   

Wood quality is an important criterion in the selection of superior genotypes when breeding for solid wood.     

Canopy structure analysis for estimating forest regeneration dynamics and growth in <Emphasis Type="Italic">Nothofagus pumilio</Emphasis> forests

•Introduction   

Silviculture systems applied in Nothofagus pumilio forests are based on opening the canopy to stimulate natural regeneration by modifying light and soil moisture. The objective is to evaluate regeneration dynamics of N. pumilio along different forest canopy and solar radiation gradients.     

Laboratory characterization of firebrands involved in spot fires

• Introduction  

Wildfires are considered the most important disturbance in the Mediterranean Basin, and some are propagated over long distances due to lift-off and ignition of firebrands.     

Climate/growth relationships in a <Emphasis Type="Italic">Pinus cembra</Emphasis> high-elevation network in the Southern French Alps

•Introduction  

In the context of climate change, assessing climate–growth relationships is of high importance in order to understand how forest ecosystems evolve and to test climate models at regional scale.     

Carbon in heartwood,sapwood and bark along the stem profile in three Mediterranean <Emphasis Type="Italic">Pinus</Emphasis> species

• Context   

Understanding biological processes in forests is necessary to orientate ecosystem management towards potential C sequestration. To achieve this, information is required about changes in forest biomass C pools, including the stem components (bark, sapwood and heartwood).     

A case study of <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> fingerprinting for breeding

• Introduction  

Tree genetic improvement programs usually lack, in general, pedigree information. Since molecular markers can be used to estimate the level of genetic similarity between individuals, we genotyped a sample of a Portuguese Eucalyptus globulus breeding population—a reference population of 125 individuals—with 16 microsatellites (SSR).     

Impacts of tree canopy structure on wind flows and fire propagation simulated with FIRETEC

Introduction   

Forest fuel management in the context of fire prevention generally induces heterogeneous spatial patterns of vegetation. However, the impact of the canopy structure on both wind flows and fire behavior is not well understood.